Final answer:
Faraday and Henry discovered electromagnetic induction in Physics.
Step-by-step explanation:
The subject of this question is Physics. Faraday and Henry discovered electromagnetic induction, which refers to the process of using a changing magnetic field to induce an electric current in a conductor. This discovery laid the foundation for many important technologies like electric generators and transformers. The other options listed in the question, such as Watt's law, electrical potential, and electromotive force, are also related concepts in the field of Physics, but they were not specifically discovered by Faraday and Henry.
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